


Luminance

by Corvid_Knight



Series: Demonstuck [40]
Category: Homestuck
Genre: Demonstuck, Look he's a giant moth and glowing boyfriend is Sexy, M/M, Safeword Use, barely offscreen, everything in this fic is either a very good or very bad decision, mating signals?, not smut, offscreen sexual content, the urge to title this fic Lämp is nigh-unbearable
Language: English
Status: Completed
Published: 2019-03-12
Updated: 2019-03-12
Packaged: 2019-11-16 03:24:50
Rating: Not Rated
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 4,512
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/18086564
Author URL: https://archiveofourown.org/users/Corvid_Knight/pseuds/Corvid_Knight
Summary: In which D gets hit over the head, chloroformed, used in about half of a magic ritual, and reminded that his boyfriend is Mothman in what isabsolutelythe best way possible.(warning for just barely offscreen sexual content!)





	Luminance

God, you must be getting old. Once upon a time you would've been hyperaware of everyone in a parking lot, the precise location of every car, human, bird and leaf within fifty feet in any direction, tracking possible movements for anything bigger than a doberman and deciding what weapon you might need to use to neutralize whatever threat arose. 

Of course, the fact that you don't do that anymore might have less to do with the twenty years in between and more to do with the fact that you've been on low-dose meds to handle the less useful side of ADHD for like half of it. But hey, it's fun to make jokes about that shit, right? Like, aging in general. For you at least. Makes Grey laugh—he won't give you an exact number, but your lover has to be around three centuries older than you are, maybe more. You've found documents from the organization that he founded dating back to the fucking 1730s; he's the old man here. 

But see, that does not make you any less of an idiot for not seeing the glint of metal on the hand of the girl—and she is a girl; you're not totally sure she's old enough to drink—who's sitting on the hood of the pickup next to yours. In your defense, the way she's posed herself makes her look like part of the scenery—a not-quite-model in a tank top with the fuckin' American flag on it, hair bleached out blonde and pulled up in a ponytail so tight you can't believe it doesn't hurt, cutoff denim short shorts that show off stunningly long legs with the kind of tan that only comes from nude sunbathing or a tanning bed. (You're guessing it's the latter.) 

Can you really blame yourself for not noticing the brass knuckles? She's _so_ not your type. And you have a wonderful, amazing, hot boyfriend back home. A boyfriend who'd be very disappointed in you right now, because not only did you not notice this chick's obvious weapon, you turned your back on her long enough for her to hop down off the hood of the truck, pad up behind you on bare feet (like, seriously? The pavement's gotta be hot as fuck) and slug you in that sweet spot at the nape of your neck with those goddamn brass knuckles as you're trying to dig your keys our of your pocket. 

It doesn't knock you out, but the world goes tilted and then completely sideways as everything in your body decides that it needs to respond to the disruption in your normal cranial routine by giving you a burst of black and white fireworks across your vision, almost bright enough to dull the pain. (Almost. You think she might've cracked your skull, holy fuck.) You're aware that you're lying in a spreading puddle of liquid, but it's almost certainly the result of the case of soda you just fucking bought for Davepeta meeting the pavement at whatever speed results from you letting go of the damn thing. 

You didn't notice her, and that was your mistake, but she didn't knock you out, and that's _hers._ At least you assume it was, until she kneels down beside you in one graceful movement that you recognise as coming from either ballet training or fighter's drills, fishes a plastic baggie out of the back pocket of those stupid tight shorts that you wish _you_ were wearing, and dumps the damp piece of cloth inside directly onto your face. 

It smells of sweetness, rot, and chemicals, and by the time she puts her hand palm-down across your mouth and nose to hold the rag there more securely, your head is already spinning badly enough that you can't move to shove her away. The hot sun and hard pavement go away very, very quickly.

* * *

You come back to consciousness somewhere that's the fucking antithesis of the sunny parking lot.

Dark? Check. 

Cool? Check.

Headache? Check. (Duh. Homebrewed chloroform sucks.)

Cold metal against your bare back? Check, apparently. Where the fucking hell are your clothes. Why is the only thing you're wearing the leather straps holding you to this god damn table. 

The next question is probably "why is the table metal" but, unfortunately, you have a pretty good idea why. The arcane symbols painted across the ceiling above you in something dark and smeary kind of tip you off. So does the smell in here; even past the the olfactory ghost of the shit Miss Redneck Seductress drugged you with, you can pick up the scent of copper pennies left out to decay. 

You guess you could move on to "what the fuck do they need my blood for," but the answer would probably be "magic." Like there would be more specifics, but you're buckass naked on a metal table in a room lit only by....

Huh. Actually, what the fuck is the light source in here? What, there's some kind of lighting system under the table? That's the only thing you can think of that'd throw shadows like this, especially since you can't actually _see_ any source when you turn your head. 

At least you _can_ turn your head; that success inspires you to test the straps holding your limbs down. 

It's a no on the getting free on your own, though. Dammit. You still try for a couple more minutes, jerking against the metal like you're gonna suddenly be able to do something more than give yourself rub burns and bruises. 

Then you huff and go limp again, and wait for somebody to show up. 

God, you wish you had some painkillers right now.

* * *

Yes, you fall asleep. What? The cultists or whoever the fuck grabbed you are lazy shits who think it's okay to just leave their kidnapped damsels strapped to tables in creepy dark rooms. That, or maybe they're just otherwise occupied. 

Like, with your kids. That's what makes you jerk awake, actually; the faint sounds of either Hal or Dirk shouting at someone a couple rooms away. You're guessing it's Hal; Dirk would be questioning whoever the fuck it is, but Hal's totally up for just roasting the shit out of the guy he's fighting, and that's what this sounds like. Too bad you can't actually pick up anything but the general tone—that shit sounds funny as fuck. 

You still try to listen, though. And you keep working your wrists against the straps, even though you know it's just gonna leave you with sore spots later. Look, if you're still stuck here when the kids find you, they're gonna tease you for _weeks._

By the time the door slams open, you've made absolutely no headway, but that's okay because Grey's the one who you see when you snap your head around. 

"Oh thank fuck." You grin at him like he's the one who stripped you down and tied you to a table. "Hey, hot stuff. Lil' help here?" 

"I—oh." He's not moving. Why the fuck is he not moving? Is there an actual reason that he's just staring at you with eyes that flicker from dark warm brown to crystalline scarlet and back again, mouth working like he's struggling to frame words? You feel like there probably is, and that you're not going to like it at all. 

"Babe. Grey." You lift your head and let it drop back down on the metal surface of the table (and _instantly_ regret that, both from the way the sound seems to echo inside your skull and the immediate pain from the impact.) "Get this shit the fuck off me? Please?" 

He still doesn't react for a maddeningly long moment. Then he shakes his head and draws the long knife you gave him for what you assigned as his birthday, coming to lean over you. _Still_ doesn't start cutting the goddamn straps. 

"D." 

"What!" 

"Did you know you're glowing?" 

"Wh—" No. That's ridiculous. Except you lift your head and actually look at your body and holy _shit_ , okay, the faint luminous aura coating every inch of visible skin (all of it) explains why you couldn't see the light source for this room. You _are_ the light source. "Hey, what the fuck?" 

"Gorgeous," Grey mumbles, low enough that you question what the hell you just heard him say. Before you can do any actual questioning about it, he puts one hand high up on your leg to hold you still and slices through one of the straps holding you with a quick, smooth motion that brings the blade close enough to your skin for you to feel the warmth of metal that's been sheathed so close to his body. 

Shit. _Shit._ Goddamn sexy cryptid boyfriend with his goddamn sexy knife, giving you a boner when you don't know where your pants are. And he knows what he's doing! You know he does, he wouldn't be rubbing gentle lil' circles into your thigh if he didn't know _exactly_ what he's doing to you, this is one hundred percent on purpose. 

It takes Grey maybe a full minute to sever every strap holding you down; he takes his hand off your thigh and you reach up to twist a double handful of his shirt up, pull him down and yourself up until you can reach his mouth. 

Kissing him is always an experience. Even when it's the quick lil' smooches that you do when the kids're around, you love every kiss you can give or steal or beg from Grey, no matter how many you get and give. But see, this is something _special_ —you're the one who initiates it but he's already met you halfway, the knife clattering on the metal table as he drops it in favor of hooking both hands under your thighs and lifting, letting you wrap your legs around his waist as he ravishes your mouth. 

Ravishes. That's _such_ a good word—it's exactly what you want him to do to you. Hell, you're already halfway there, all you gotta do is get his pants off—

Oh, you fucking horny disaster. _No._

Grey growls when you get your hands up between the two of you, put your palms flat on his chest and push yourself back. It's a possessive sound, the kind of thing that makes you want to go _yeah okay we should keep going actually_ , and it's a real struggle to shake your head clear and meet his eyes instead. 

Oh, by all that's holy. That's not just lust in those dark eyes, not even hunger—you know Grey well enough to know that he's fucking _starving_ for you right now, that if you hadn't pulled back he sure as hell wouldn't have. What the fuck kinda magic did those idiots get you tangled up in, anyway? Like, sex is a pretty damn potent source of power if you use it right, but Grey should be immune to just about everything. This seems like a cause for major concern. 

"Babe. Grey. Robert." When he rolls his eyes, you stifle a laugh and reach up to pat his cheek. "Hey, I had to check you weren't all zoned out on me, okay? This ain't a great place 'n time to fuck, darlin'." When he just blinks and lifts one hand to cradle the back of your head, carding through your hair and trying to nudge you back in, you very nearly take that sentence back. But. "Grey, the kids are gonna burst in here looking for me sooner or later—"

Damn, that gets another possessive growl out of him. It's maybe the sexiest thing you've ever heard, that he's that protective of _you_. It also gets him to loosen his grip on you so you can slide back down onto the table, which ain't one bit sexy—Grey may be giving you that hungry-eyed look again, but you're more concerned with the fact that the surface's already lost what little heat it leached from you; your bare ass is on freezing metal, and it's _horrible._

Hopping up off the damn thing means that you smack into Grey, which means you have to swat his hands away before you start really liking where they're heading. "No. Nope. Give me your shirt." 

"What?" 

"Shirt. Now. I'm not running the god damn risk of bumping into one of my kids and having—" Oh, you're gonna regret it if you let what's in your head come out of your mouth. "—my fucking glowworm on display for the world to see!" 

Dammit. 

Grey stares at you. Glances down, presumably to check the veracity of the term you just used. (And yes. It's glowing. More brightly than the rest of you, actually; you're guessing your luminescence is brighter where there's a concentration of blood.) Then he smiles (ohfuckstillsexy) and pulls his plain blue t-shirt off over his head in one smooth motion, tossing it at you. 

You don't even kind of come close to catching it. The fucking thing settles down over your head, blinding you and tangling you up instantly. Means that the first warning you get that he's gonna pick you up is when he _does_ it, swooping you off your feet and gathering you into his arms like a bride being carried across the threshold. 

(The fact that he's definitely gonna carry through on the newlywed metaphor is something you're trying not to think about, at least not until you've got him somewhere alone. This is made markedly harder by the fact that you're mostly naked, being cuddled against his bare chest, and can smell nothing but the sweet cinnamony scent of his shirt.) 

Oh for fuck's sake. You struggle a lil' bit more, get your head through the head hole and pull the hem down far enough that you might not get arrested for indecent exposure, and resign yourself to being carried out of wherever the fuck this is.

* * *

You guess you could've just gone without the limited modesty of Grey's shirt, because he manages to maneuver around any possible encounters on the way out of the building. This is probably aided by the fact that they seem to have stored you as far off from everything else as is humanly possible; hell, most of the narrow hallways he carries you down ain't even lit. From what you can see by your own current luminescence, some of them appear to have been just, like, dug into the earth and halfassedly shored up with two-by-fours. 

On the one hand you applaud these idiots' determination, but on the other hand there is no _way_ this shit is safe. The rooms themselves, maybe—there wasn't any way to tell that the room they had you in wasn't in a lab somewhere—but the passages between them are worrying as fuck. 

The fact that Grey eventually comes to a set of ancient-looking stone stairs is comforting. The fact that the stairs lead up to a goddamn Airstream in the middle of a fucking _trailer park_ is very fucking not comforting. 

"No. You're serious? _This_ is the kinda people that kidnap me these days?" You can't believe this shit. You're physically incapable of belief right now. "This isn't fucking happening—" 

"Is this really the strangest thing you've ever been through, love?" Grey murmurs in your ear, finishing the question off with a kiss to the sensitive place where your jaw joins your neck. It's distracting enough that you barely notice he's shifted his grip to support you one-handed, using the other to get the door to the backseat of your truck open. 

He won't let you cling to him; goddamnit but sometimes you wish he wasn't so fucking strong. Then again, if he couldn't just pick you up and arrange you like he wants, you'd have to wait a whole lot longer to be lying on your back across the seat, Grey's shirt pushed up past your hips, staring up at him as he meets your eyes and licks his lips and leans down to—  
His phone goes off. With _your_ ringtone. You groan, lay back and grab the damn thing off the console between the front seats, answering it just as Grey actually starts doing what you kind of can't believe he wants to do _now_. 

" _Grey?_ " 

Ah, _shit._ You bite down on your lip until you start tasting blood before you even try to answer. It does not help. "Di— _ahhh,_ fuck—Dirk?" 

" _...D?_ " 

"Yes, D, I'm ali—Grey, _please_ —I'm alive 'n in one piece, it's all good—" God fucking damn it, that's not what you meant by _please_! That's the literal fucking opposite of what you meant by please and good _lord_ you will actually die if he stops. "Dirk, gonna call you back—" 

" _It's Hal—where the fuck are you?_ " 

"Uh, Grey's gonna take me home—" 

Grey makes a deeply humming growl when you say his name. The noise that comes out of you leaves very little doubt as to what you're doing right now. 

" _...are either of you actually driving._ " 

"Not yet, no!" 

" _Because if you crash the truck because somebody's giving somebody a blowjob, Karkat's going to eviscerate you._ " 

That's not a sexy thought. Which is good, because you need to think of something unsexy to be able to say, "Yeah, yeah, hanging up now," hit the disconnect button, and drop the phone somewhere on the floorboard in favor of tangling both hands up in Grey's straight black hair and hanging on for dear life.

* * *

You've had a couple individuals try to drag your soul out of your body before. What Grey does is kind of like that, except in a _good_ way. An _excellent_ way. A _you almost let yourself think it'd be a good idea to let him fuck you in the truck_ way. 

However, that's the exact opposite of a good idea, and the two brain cells that're still functioning after Grey's attentions are just barely sufficient to talk him out of everything else he wants to do to you. A large part of your brain is hella disappointed when he gives in, too. 

The rest of your brain just wants to curl up on the backseat and go to sleep with Grey's shirt pulled up almost over your face. That's nice, you like that. Comfy. 

The result of this decision is that you have absolutely no idea how long it takes to get from the trailer park to the safehouse—hell, if Grey didn't get out of the driver's seat and immediately come around to scoop you up out of your comfortable spot in the backseat, you probably would've just stayed there until the last of the air conditioning wore off. But he picks you up, and you reluctantly come halfway back to being awake, and he kisses you and that's enough to get you the rest of the way. 

"Fuck, you're perfect," you mumble when he pulls away from you, presumably to get the door open. (There's no way you're opening your eyes to check.) "Hey, am I still—" 

"Beautiful?" 

"Glowing. Am I still glowing." 

"Brighter than the stars." Oh, _fuck_ , that deep growling note in his voice...wait, the thing he said ain't exactly what you were hoping to hear. Fuck. 

"Goddamnit—okay, I need a shower." 

"Later." 

"Grey, you horny dumbass—" 

He laughs and silences you with another kiss, and by the time he lets you pull away you've completely forgotten that you _had_ objections to his plans, let alone what they were.

* * *

In the shower nearly an hour later (having kicked Grey out because he apparently isn't gonna get tired of getting frisky at this point) you finally admit defeat. Mostly because all of the scrubbing you've done has accomplished basically nothing, other than to confirm that the luminance isn't actually limited to the surface of your skin; you suspect that the more brightly glowing droplets you managed to bring to the surface when you scrubbed long and hard enough were, y'know...blood. 

You step out from under the water and experimentally lick the brighter spot on your arm. Yep, that's blood. Ew. Doesn't stop you from licking it again, just to check. Maybe you just tasted wrong—

"There's better things you could be using that tongue on," Grey remarks from the doorway. 

You instinctively grab for the shower curtain (because that makes perfect fucking sense. Conceal yourself from your own goddamn boyfriend with a transparent plastic shower curtain) and get it wrapped halfway around yourself before you realize that this is actually making things markedly worse. Better. Okay, look, Grey's getting that hungry-eyed look again, even though you're soaking wet and _still_ glowing, maybe even brighter than before with the weird refraction and diffusion of the water and the shower curtain, and honestly? Shower sex with a guy who's capable of keeping you from slipping and breaking your neck is hot as hell. 

You let go of the shower curtain and take a step back into the still-running water, giving him the most perverted smile you can manage. "Alright, c'mon. Come tell me where to use my tongue, daddy." 

The fact that Grey doesn't wince at you invoking that kink in this house gives you a clue about just how much your current state's affecting him. If that failed to sink in, the way he pins you up against the wall drives it home even less subtly, and you fucking _love_ it.

* * *

...it's probably close to an hour before you finally start whining at Grey to take you somewhere dry. By that point he's fucked you against the shower wall, lifted you out and set you on the counter and made out with you for however fucking long it takes for the bathtub to fill (your time sense is going even more screwy than usual but you know it was long enough that you were begging for him again by the time he picked you up and stepped into the water and settled into that hot warmth without ever letting you off his lap), and spent long enough in aforementioned tub that the water went lukewarm.

It's also glowing. Just a little bit. Thinking about _why_ it's glowing would be kind of gross, if you weren't pretty damn close to completely worn out. 

Anyway, moving on from speculations on the genetic-material-to-water ratio! 

Grey wraps you in one of the huge towels that Jr "accidentally" ordered. Not that you believe that they assumed the dimensions were in feet instead of meters; the kid's smarter than that. They just wanted something big 'n fluffy. Honestly, you like it too; it doesn't take much effort to make you completely disappear in it. Makes you feel even more like Grey's bride, as he carries you out of the bathroom and to the bedroom...

...where he lays you down and curls around you, pressing soft kisses along your jaw, down your neck and to your chest. By the time he gets to your collarbone, they're not quite as soft; it's enough that he's got you squirming, hands twisted up in the sheets, shuddery gasps barely drawing enough air into your lungs to let you moan out for him. 

But it's, uh. Shit. Okay, you want him, you _always_ want him, but the thought of following this chain of actions to its logical conclusion (which you've reached enough times in the last couple hours that you lost track) is...

"Piano." Fuck, you don't even know if he remembers setting this deal up. Not like you safeword a whole lot. "Grey, piano, alright, I'm tapping out—" 

Yeah, he remembers. Grey goes still the second you say it; by the time you clarify that you're done, he's already sitting up, sweeping you into his arms, dark eyes phasing to insectile for an instant as he scans your face. "I hurt you—" 

"Nah." Reaching up to put your hands on his face isn't actually gonna work to smooth that worry away, but you do it anyway. "I mean, maybe in the fun way, but that don't count. I'm okay. Just need a breather. A nap. Maybe a couple aspirin." 

That gets a soft, deep laugh, at least. One more sound that trips all your love switches and some of your horny ones; god, you're such a slut for him? Like, you _know_ that you should just give him a cheek kiss, but here you are wrapping your arms around Grey's neck and kissing him as deep as you can, even though that means that his hands go to the curve of your spine and guide you down, gentle and fucking _irresistible._

Well, maybe not totally irresistible. 

You jerk your head back and get both hands on his chest, pushing back until he lets go. It only takes a moment. Grey doesn't move to stop you as you gather up the blanket, wrap it around yourself like a regal garment, and sweep less-than-gracefully out of the bedroom and in the general direction of the nearest couch.

* * *

_Someone_ has his hand on your shoulder, and god damn but you're still not up for this shit! Not even when you actually wake up all the way! 

"Piano, g'dammi', _piano_..." That comes out slurred almost into illegiblity, but a soft laugh from Dirk tells you that at least one person totally understood it. 

Well, fuck. 

You roll over and open one eye. 

"It lives," Hal says as soon as you do. "And I think it just tried to safeword on us." 

"Did _not_." Denying it will get you nowhere, not with Dirk, Dave, and Hal all grinning down at your blanket-burritoed self like this is the best comedy routine they've ever seen. How the fuck does he even know that's your safeword? "Lemme sleep, guys, cmon..." 

"Hey, you're the one who decided to nap on the couch!" Davepeta squeezes through the small gap between Hal and Dave, dropping into a crouch that puts them on the same level as you. You really wish they hadn't do that; there's blood streaked across their face and into their hair, like they took a fucking bath in that shit. 

"Oh dear fucking _fuck_ , kiddo." Closing your eyes doesn't really help; you're gonna have nightmares about that sharp-toothed smile surrounded by gore. You know you are. "What'd you do?" 

"Hey, when somebody comes at me with a knife I rrrreact!" Davepeta rolls the _r_ until it's almost a purr; when you open your eyes they're in the middle of rubbing one paw—no, hand; goddamn but they're more animal than usual right now—across their face, scrubbing off a little blood and licking it off their skin. 

Holy shit that's grosser than contaminated bathwater. "...Hal, clean your sibling up." 

"They bite, so no." 

"Your body is a construct—" 

"It still hurts?" 

"Hey D," Davepeta chirps brightly, starting another sweep across their face with a freshly licked-clean hand, "did you know you're glowing?" 

...y'know what, rolling over and going back to sleep is the most sane thing to do here. Bye, y'all.

**Author's Note:**

> this fic garnered arguably the worst anon i've ever had on tumblr so thanks i guess?


End file.
